Dye sublimation is a known process for printing images on mediums such as fabrics, paper, etc. This process involves “heat activated” or “subliming” dies which turn from a solid into a gas at a specified time, temperature and pressure. Dye sublimation is especially advantageous for printing images on fabrics. Indeed, when transferring an image onto fabric using a dye sublimation printing process, the dye is more than simply deposited on the surface fabric; it actually penetrates the depth of the fabric and dies its fibres. This results in stable and durable prints, which is desirable when printing images on clothes, since the clothes can be repeatedly machine-washed while causing minimal to no fading of the image printed thereon.
Traditionally, dye sublimation involves the two-step process of “transfer printing”. Firstly, an image such as a photograph, text, or any other graphic design, is printed in reverse format onto an intermediary medium called a transfer substrate, using sublimation dye-containing inks; this transfer substrate can for example be a sheet of paper called a transfer sheet. During the transfer of the image to the transfer substrate, the dye is not sublimed; the dye is rather merely printed or deposited superficially onto the transfer substrate but is not permanently bound thereto.
The inked side of the transfer substrate is then positioned to face the permanent substrate (e.g. the front of a T-shirt), upon which the image is to permanently appear. A heating device, such as a heat press, is then used to apply elevated temperature and pressure to the transfer substrate, to cause the dye to sublime and diffuse into the depth of the permanent substrate where it permanently bonds.
The permanent substrate may be any type of material which will accept and retain the transferred image, including but not limited to fabric. For example, dye sublimation printing can be used to generate items such as T-shirts, coffee mugs, mouse pads, etc.
Initial dye-sublimation technology used ribbons to carry the sublimation dyes in solid form. More recent technology employed sublimation inks in liquid form. With either print set-up, it is necessary that the image be transferred onto an intermediary transfer substrate before being permanently transferred to the permanent substrate.